Mozilla testing new Firefox Private Browsing mode

Firefox developer Mozilla has announced that it is opening a new Private Browsing system for testing, promising to develop its browser to become the number-one choice for those who would prefer to not be tracked online.

The concept of a private browsing mode, where a new browser window can be opened in such a way to visit websites without permanent cookie or history storage, began in 2005 with Apple's Safari. Since then, all major browsers have implemented their own variant of private browsing, but few make any attempt to actively block the tracking of its user across the web. That's something Mozilla is looking to resolve, via a new private browsing mode available in its pre-beta Firefox releases now.

'Our hypothesis is that when you open a Private Browsing window in Firefox you’re sending a signal that you want more control over your privacy than current private browsing experiences actually provide,' the company explained in its announcement. 'The experimental Private Browsing enhancements ready for testing today actively block website elements that could be used to record user behaviour across sites. This includes elements like content, analytics, social and other services that might be collecting data without your knowledge. In some cases, websites might appear broken when elements that track behaviour are blocked, but you can always unblock these if you want to view the website normally. Private Browsing in pre-beta Firefox also has a Control Centre that contains important site security and privacy controls in a single place.'

Although the new features are described as 'for testing only' and should not be relied upon for absolute privacy, it's a step the company is clearly hoping will help reverse the browser's fortune: in recent years Firefox's market share has been eroded by Google's Chrome, and with early adopters singing the praises of Microsoft's new Edge browser - the default for Windows 10 - the battle to become users' default browser has never been more fiercely fought.